The present application relates to the field of radiation imaging. It finds particular application with computed-tomography (CT) security scanners configured to generate a three-dimensional image of an article under examination. It also relates to medical, security, and other applications where the identification of articles using radiation technology (e.g., x-ray systems, gamma-ray systems, etc.) may be useful.
Imaging systems (e.g., also referred to as radiation imaging systems) such as computed tomography (CT) systems, diffraction CT, single-photon emission computed tomography (SPECT) systems, digital projection systems, and/or line systems, for example, are utilized to provide information, or images, of interior aspects of an article under examination. Generally, the article is exposed to radiation comprising photons (e.g., such as x-ray photons, gamma ray photons, etc.), and an image(s) is formed based upon the radiation absorbed and/or attenuated by interior aspects of the article, or rather an amount of photons that is able to pass through the article. Generally, highly dense aspects of the article absorb and/or attenuate more radiation than less dense aspects, and thus an aspect having a higher density, such as a bone or metal, for example, may be apparent when surrounded by less dense aspects, such as muscle or clothing.
Imaging systems are utilized in a variety of fields to image aspects of an article not readily visible to the naked eye. For example, imaging systems are used in security applications to identify potential threat items, which may include weapons and/or explosives, concealed within a suitcase, bag, person, and/or other article, for example. While automated threat detection systems are available in some imaging systems, oftentimes it is the responsibility of an operator viewing an image of an article to determine whether the article contains a potential threat item (e.g., and thus requires additional inspections, such as a hands-on inspection). Accordingly, operators at security checkpoints and other venues are required to be attentive. Such attentiveness, combined with the knowledge that few articles actually contain a threat item, may lead to fatigue and/or other distractions that potentially result in an article containing a threat item passing through the system undetected.